Stellar distances and planetary masses of extrasolar planets listed on www.exoplanet.eu as of 5 April 2015. Symbols indicate the discovery method of each planet, six solar system planets are shown for comparison. Note the cluster of red dots around 1 AU along the abscissa and between 1 and 10 M_Jup along the ordinate. These super-Jovian planets might be hosts of Mars-mass moons. The shaded region denotes the solar habitable zone defined by the runaway and maximum greenhouse as per Kopparapu et al. (2013).